I've found out how to run the command for carcass, and also I found a post from 2004 where keshire explained me what meant the things inside the .car, so I've done some progress.
ShadyD is giving me some help, he was able to make new animations with 3dsMax and he's trying to refresh his memory. We have been able to at least compile the new_anim.xsi into a new_anim.gla with a .car file, however, glamerge give us an error because it says that the number of bones is different, so in ModView the model deforms like a demon for the new animation.
Does the number of bones being different means that the OJP_Anim_Template.xsi is wrong? I'd like to know the answer.
I hope we can find our way out to add the new animations. Once I get it I'm gonna do a tutorial and post it in this thread, since this one is really confusing and frustrating ending in a dissapointment at least for me.